A variable core model of a moving crystal dislocation was proposed and used to derive an expression for the Peierls stress. The dislocation width varies periodically as a dislocation moves through the lattice, which led to an expression for the Peierls stress in terms of the difference of the total energies in the crystal corresponding to stable and unstable equilibrium configurations of the dislocation, rather than the difference in the misfit energies alone. Results for both edge and mixed dislocations were given and proposed to be used in conjunction with ab initio calculations.

Variable Core Model and the Peierls Stress for the Mixed (Screw-Edge) Dislocation. V.A.Lubarda, X.Markenscoff: Applied Physics Letters, 2006, 89[15], 151923 (3pp)